About PaymentMath

We build free calculators that show what a payment really costs, in plain English.

Big purchases like cars are usually sold by the monthly payment. That number hides how much interest you pay, how taxes and fees add up, and what a longer loan really costs. PaymentMath puts the whole picture on one screen so you can walk into a dealership or bank already knowing the numbers.

How our calculators work

• We use the same standard amortization formulas lenders use, and we test our math against known reference values.
• Every calculation runs in your browser. What you type is never sent to our servers.
• We keep pages fast and uncluttered. Ads, when shown, stay out of the way of the calculator.

Our limits

Our results are estimates for education and planning. They are not financial advice or a loan offer. Your actual rate, taxes, and fees depend on your lender, your credit, and where you live.

Get in touch

Found a bug or have an idea for a calculator? Contact us. We read every message.